A Schiff base‐grafted nanoporous silica material as a reversible optical probe for Hg2+ ion in water

• Published in: Applied organometallic chemistry 2017-12, Vol.31 (12), p.n/a
• Main Authors: Afshani, Jafar, Badiei, Alireza, Karimi, Mehdi, Lashgari, Negar, Mohammadi Ziarani, Ghodsi
• Format: Article
• Language: English
• Subjects: Chemical synthesis; Chemistry; Emission analysis; Fluorescence; Hg2+ ion; Imines; Mercury (metal); nanostructures; optical material; photoluminescence spectroscopy; Quenching; Selectivity; Silicon dioxide
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.3856

A novel organic–inorganic silica‐based fluorescent probe was designed, synthesized and characterized by different techniques such as XRD, BET, TGA, and FT‐IR. The fluorescence properties of the probe were studied in the presence of a variety of metal‐ions in water. The results revealed that various metal‐ions negligibly vary the emission intensity of the probe except for Hg2+, which quenched the intensity dramatically. The selectivity of the probe toward Hg2+ ion was further investigated in the presence of common competing metal‐ions and the results demonstrated the high selectivity of the probe toward Hg2+ ion. The fluorescence emission of the probe was also studied as a function of the concentration of Hg2+ ion. A nanomolar limit of detection was estimated for Hg2+, indicating a high sensitivity. Furthermore, the probe showed INHIBIT‐type logic behavior with Hg2+ and H+ as inputs. Also, the optimum pH range was studied in addition to reversibility and real world applicability of the probe. A novel fluorescent probe based on functionalization of SBA‐15 with a Schiff base was synthesized and displayed a high selectivity for Hg2+ over a variety of metal ions in water with a nanomolar limit of detection. Furthermore, the probe showed INHIBIT‐ type logic behavior with Hg2+ and H+ as inputs.